Add missing bin/merge.c

bin/merge.c

@@ -0,0 +1,90 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <cammy/image.h>
+#include <cammy/photo.h>
+
+#include "commands.h"
+
+static void usage(int argc, char **argv, const char *message, ...) {
+    if (message) {
+        va_list args;
+
+        va_start(args, message);
+        vfprintf(stderr, message, args);
+        va_end(args);
+         fprintf(stderr, "\n");
+    }
+
+    fprintf(stderr, "usage: %1$s merge input.png output-r.png output-g.png output-b.png\n", argv[0]);
+
+    exit(1);
+}
+
+int cammy_merge(int argc, char **argv) {
+    cammy_image *image_in_r,
+                *image_in_g,
+                *image_in_b,
+                *image_out;
+
+    if (argc < 3) {
+        usage(argc, argv, "No red input file provided");
+    } else if (argc < 4) {
+        usage(argc, argv, "No green input file provided");
+    } else if (argc < 5) {
+        usage(argc, argv, "No blue input file provided");
+    } else if (argc < 6) {
+        usage(argc, argv, "No output PNG filename provided");
+    }
+
+    if ((image_in_r = cammy_image_open(argv[2])) == NULL) {
+        goto error_image_open_r;
+    }
+
+    if ((image_in_g = cammy_image_open(argv[3])) == NULL) {
+        goto error_image_open_g;
+    }
+
+    if ((image_in_b = cammy_image_open(argv[4])) == NULL) {
+        goto error_image_open_b;
+    }
+
+    if ((image_out = cammy_image_merge(image_in_r,
+                                       image_in_g,
+                                       image_in_b)) == NULL) {
+        goto error_image_merge;
+    }
+
+    if (cammy_image_save(image_out, argv[5]) < 0) {
+        goto error_image_save;
+    }
+
+    cammy_image_destroy(image_out);
+    cammy_image_destroy(image_in_b);
+    cammy_image_destroy(image_in_g);
+    cammy_image_destroy(image_in_r);
+
+    return 0;
+
+error_image_save:
+    cammy_image_destroy(image_out);
+
+error_image_merge:
+    cammy_image_destroy(image_in_b);
+
+error_image_open_b:
+    cammy_image_destroy(image_in_g);
+
+error_image_open_g:
+    cammy_image_destroy(image_in_r);
+
+error_image_open_r:
+    return 1;
+}